In mobile communication which has become widespread toady, communication with high accuracy is required in various channel environments. Further, as a means to realize communication with high accuracy even in severe channel environments, error correction encoding processing is performed on transmission data.
In 3GPP (see Non-Patent Literature 1), a plurality of fixed information blocks formed with a predetermined number of bits K are formed from a series of transmission sequences, and error correction encoding processing is performed per this fixed information block. There is no problem when that series of transmission data sequences can be divided by K. In contrast to this, when that series of transmission data sequences cannot be divided by K, bit padding is performed on that series of transmission data sequences to arrange padding bits in the head part of that series of transmission data sequences, so that the total number of bits is made a number that can be divided by K. Then, encoding processing is performed on the data sequences in which padding bits are arranged, per fixed information block. By this means, it is possible to perform encoding processing of constraint length K uniformly.
Further, error correction encoding schemes include convolutional encoding scheme (for example, see Patent Literature 1) and turbo encoding scheme (for example, see Non-Patent Literature 2).
Then, afterwards, modulation processing is performed in modulation section on codewords obtained by error correction encoding processing, and before the modulation processing, puncturing (i.e. decimation) is performed to perform rate matching. In 3GPP, there are stipulations about a turbo encoder and a rate matching apparatus for performing puncturing. Further, there is a stipulation that when performing rate matching after performing puncturing processing, information bits (i.e. systematic bits) are not deleted, but only parity bits are deleted out of turbo-encoded data sequences.